Virtualbox V7 problems with Windowow guests crashing on boot.

I'm not asking for help here but posting in case anyone else has had this problem.

When VirtualBox V7.0 was released last month I tried updating from V6. This was not successful in that although Linux guests ran successfully both W10 and W11 guests crashed during boot. It was not immediately obvious what the issue was so I decided to wait for an update.

V7.04 arrived this month and also had the same problem. I decided to dig more deeply.

Trawling through the logs suggested the crash occurred at about the same time as the NVIDIA GPU was activated. I switched from NVIDIA to Intel Integrated graphics with a similar result.

Further investigation showed that one setting, a checkbox for 3D graphics on the Display tab determined whether a GPU was used. Unchecking that allowed both W10 and W11 guests to boot with some loss of functionality, mainly the ability to display transparency or acrylic effects.

The virtual graphics driver is in an extension pack which is applied from within the running guest so I was now able to upgrade that to the latest version. With the latest diver installed I was able to turn the 3D graphics back on and boot both W10 & W11. W10 looks to be working well but W11 has some nasty artifacts, the most immediately obvious one being a completely transparent start menu.

If you have this problem it is probably best to leave 3D turned off for the moment until Oracle come up with a better solution.